JP2569558Y2 - Electrode rotation prevention device for spot welding gun - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing an electrode from rotating in a spot welding gun. In particular, it is an object of the present invention to make the entire gun dramatically compact by housing a detent shaft of a press shaft having an electrode of a spot welding gun in a front portion of the press device.

[0002]

2. Description of the Related Art As a conventional electrode detent device for a C-shaped spot welding gun, there is known, for example, Japanese Utility Model Publication No. 57-29986 "Cylinder pressure rod detent device". FIG. 4 is a drawing of such a conventional apparatus. In the device shown in the figure, a non-rotating shaft 33 fixed to the pressing shaft 32 is inserted into a guide hole 37 provided in a cylinder casing, and the guide hole 37 is inserted into the large-diameter long hole 37a having a clearance between the pressing shaft 32 and the play. A cylindrical recess 38 is provided in the casing of the cylinder 31 at right angles to the long hole 37a, and the cylindrical guide tube 39 is inserted into the recess 38 so as to be freely retractable and rotatable. The anti-rotation shaft 33 is inserted therethrough.

[0003]

However, in the conventional anti-rotation device, the anti-rotation shaft 33 is fixed to the point holder side in parallel with the pressure shaft 32, and the tip of the rotation prevention shaft is the pressure cylinder. Since the guide hole provided in the body casing side is inserted, the overall size of the cylinder is increased, which is one of the factors that hinder the weight reduction of the gun.

According to the present invention, the entirety of the gun is made compact by fixing the non-rotating shaft 33 to the front portion of the pressure device instead of passing the non-rotating shaft 33 through the main casing of the gun pressing device. Promote reduction of gun weight.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a detent shaft is fixed in front of a pressurizing device of a spot welding gun in the direction of an electrode tip in parallel with the pressurizing shaft of the pressurizing device. The rotation of the pressure shaft is prevented by passing the shaft through a guide portion provided on the pressure shaft.

[0006] The invention is characterized in that the guide portion is provided on a point holder integrally attached to a pressure shaft.

[0007]

FIG. 1 is an assembly view showing an embodiment of the present invention. FIG. 2 is a side view thereof. FIG. 3 is a view taken in the direction of arrows AA.

In the drawing, reference numeral 1 denotes a spot welding gun. Reference numeral 2 denotes a main body tube of the pressurizing device. The pressurizing device in this case is intended to be an air cylinder, but an electric motor may be used. Reference numeral 3 denotes a front cover, which is manufactured from a casting integral with the cylinder tube. 4 is a pressurizing shaft of an electrode composed of a piston rod, 5 is a bearing of the pressurizing shaft,
Reference numeral 6 denotes a point holder fixed to the outer periphery of the pressure shaft, to which a shunt 7 constituting a secondary circuit is attached. Reference numeral 8 denotes an electrode fitted to the tip of the pressure shaft. Reference numeral 9 denotes a gun arm, one of which is fixed to the pressure device side and the other end of which is fitted with an electrode 10.

Reference numeral 11 denotes a detent shaft. The detent shaft projects in the direction of the electrode tip in parallel with the electrode shaft, that is, the pressure shaft 4, and has a recess 1 provided in the front cover of the pressure device.
2 and is fixed by bolts 13. The detent shaft is guided and supported through a bearing 15 of a guide hole 14 provided in the point holder 6.

Reference numeral 16 denotes a secondary cable having two conductors fixed to the gun arm. One is connected to the gun arm, and the other is connected to the point holder 6 via the shunt 7. Reference numeral 17 denotes an operation handle.

In the apparatus according to the present invention having such a configuration, the rotation stopper shaft 11 is fixed to the front of the pressurizing device of the spot welding gun in a direction parallel to the pressurizing shaft 4 in the direction of the electrode tip. By guiding through a shunt mounting member such as the point holder 6 provided integrally, rotation of the pressure shaft can be prevented.

In this embodiment, the tip of the detent shaft is made to penetrate the guide portion of the point holder 6 at the electrode open position, but if the dimension of the detent shaft is shortened, it protrudes from the guide portion within the electrode stroke range. You can also guide without it.

[0013]

As described above, according to the present invention, instead of fixing the anti-rotation shaft to the point holder and inserting this into the body casing of the gun pressurizing device as in the prior art, the anti-rotation mechanism is pressurized. The gun can be stored as small as possible at the front of the device, and the entire gun can be dramatically reduced in size.

[Brief description of the drawings]

FIG. 1 is a side view showing a structural example of the device of the present invention, showing a partially crushed cross section.

FIG. 2 is an enlarged sectional view of the device of the present invention.

FIG. 3 is a view as viewed in the direction of arrows AA in FIG. 1;

FIG. 4 is a side view of a conventional electrode rotation prevention device for a spot welding gun.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spot welding gun 2 Main body tube of pressurizing device 3 Front cover 4 End cover 5 Bearing 6 Point holder 7 Shunt 8 Electrode 9 Gun arm 10 Electrode 11 Non-rotating shaft 12 Depression 14 Guide hole 15 Bearing

Claims (2)

(57) [Scope of request for utility model registration] An anti-rotation shaft is fixed in front of a pressurizing device of a spot welding gun in the direction of an electrode tip in parallel with the pressurizing shaft of the pressurizing device, and the anti-rotation shaft is provided on the pressurizing shaft. An electrode rotation prevention device for a spot welding gun, wherein rotation of a pressure shaft is prevented by passing through a guide portion. 2. The device according to claim 1, wherein said guide portion is provided on a point holder integrally attached to a pressure shaft.